This application claims priority of DE 198 53 366.7, filed Nov. 19, 1998, the disclosure of which is expressly incorporated by reference herein.
The present invention relates to a process for forming workpieces in a forming system having at least one forming station. Furthermore, the invention relates to an improved system for implementing the foregoing type of process.
Forming processes and the related forming systems are known, for example, from EP 04 39 684 B1 and EP 05 47 190 B1 as well as from DE 38 32 499 A1 and DE 39 05 069 A1. As a rule, these processes produce relatively large-surface workpieces from sheet metal plates by the varied forming operations, such as pressing, cutting or deep-drawing. For producing such large-surface work pieces, very large and therefore very heavy forming tools are used in most cases. Such, which forming tools oscillate at a corresponding stroke rate and the pertaining speed for achieving a large piece number.
A disadvantage of the known processes is that the large mass of these forming tools has to be accelerated and braked during each stroke, which consumes a lot of energy. Another disadvantage is the large expenditures of material and cost which are required for manufacturing the forming tools.
An even more serious problem concerns the very long development periods for the forming tools. For example, in the development of a motor vehicle, these development periods represent a very large fraction of the entire development time. Possible changes on the forming tools disadvantageously lead to high expenditures. In addition, the transportation of the workpieces from one forming station to the next is very time-consuming and causes unnecessarily high costs.
An object of the present invention is, therefore, to A provide a process and system for forming workpieces by way of which, as the result of reduced expenditures with respect to material and development, an identical or better forming result can be achieved than by means of known forming processes and systems. Furthermore, the largest possible amount of flexibility is to be achieved during the retooling, in that the adaptation to another product can take place as much as possible by means of reprogramming.
According to the invention, this object is achieved by a process in which outside the time period provided for the forming of a certain workpiece in the forming system, a machining with a local energy feed to this workpiece can be carried out.
As the result of the machining of the workpiece according to the invention with a local energy feed within the forming system outside the time provided for the forming, this step, which otherwise results in idle time, can be used advantageously for a machining of the workpieces. The flexibility of the entire forming process is increased in that the machining contour can be programmed. Furthermore, a very small mass must advantageously be moved in this case.
In the present context, a local energy feed means that the extent of the energy-affected zone or of the machining range without a relative movement for machining the workpiece is small in comparison to the dimension of the workpiece.
Constructive solutions for achieving the above object are in which at least one machining device with a local energy feed is arranged on a transport device for the workpiece wherein at least one machining device with a local energy feed is fixedly arranged in the forming system.
Both possibilities of the arrangement of the machining device according to the invention either on a transport device or directly within the forming system permit an easy implementation of the process according to the invention. As a result, one or several forming stations of the forming system can be eliminated, whereby considerable costs may be saved for the whole forming system. In addition, the space requirement for the forming system according to the invention is also reduced.
Concerning the general state of the art with respect to laser machining systems in machine tools, reference is made to DE 34 10 913 A1, DE 41 28 194 C2 and to EP 00 08 773 B1.